1. Field
The following description relates to a technology that may measure complexity of an in-loop pixel correction process using video codec parameter information in a video codec, and may enable jobs associated with the in-loop pixel correction process to be evenly distributed to encoding/decoding apparatuses for parallel correction of in-loop pixels, using the measured complexity, to improve a parallel processing speed.
2. Description of the Related Art
Due to an increase in demand for images with a High Definition (HD) level or higher, there is a need for a new encoding and decoding method to achieve a higher efficiency than provided by the H.264/Advanced Video Coding (AVC) video codec. Accordingly, recently, the Moving Picture Experts Group (MPEG) and the Visual Coding Experts Group (VCEG) are standardizing a next-generation video codec named “High Efficiency Video Coding (HEVC)” through a Joint Collaborative Team on Video Coding (JCT-VC).
In other words, the HEVC refers to the next-generation video codec that is being standardized by the JCT-VC established in collaboration with the MPEG and VCEG.
A large number of technologies are being proposed to standardize the HEVC. Among the technologies, a technology with high compression efficiency relative to technical complexity is employed. In particular, a plurality of technologies associated with in-loop pixel correction are employed, compared to the H.264/AVC. Each of the technologies associated with in-loop pixel correction is described below.
The HEVC may employ an in-loop pixel correction technology that may apply filtering to a restored image, in an order of a de-blocking filter, a Sample Adaptive Offset (SAO), and an Adaptive Loop Filter (ALF).
The de-blocking filter may calculate a boundary strength in a boundary of a Coding Unit (CU), a Prediction Unit (PU), and a Transform Unit (TU) that are located in a block larger than an 8×8 block, and may perform filtering to remove a blocking artifact occurring in a block boundary.
The SAO may be performed around an edge in an image to which de-blocking filtering is applied, or performed on a set of predetermined pixel values.
The SAO refers to a technology of dividing a region, namely a basic unit, into a plurality of pixel sets, obtaining an average offset in pixels included in a corresponding set, adding the average offset to restored pixel values, and enabling a restored image to be similar to an original image.
The ALF refers to a technology of obtaining a filter to minimize a mean square error between an original image and an image to which the SAO is applied, performing filtering using the filter, and minimizing an error in a restored image.
The ALF may transmit an on/off flag regarding whether filtering is applied in a quad-tree block unit, and may perform more effective filtering.